Tri-esters of hydroxy alkyl thio succinic acids



.and phenethyl groups. trated by a phenyl group and where n is an Patented Oct. 6, 1953 2,654,773 a TRI-ESTERS OF HYDROXY ALKYL THIO SUCCINIC Richard 0. Zerbe, Nitro, W. Va.,

santo Chemical Co corporation of Delaware ACIDS assignor to Monmpany, St. Louis, Mo., a

No Drawing. Application July 22, 1949,

Serial No. 106,319

14 Claims. (Cl. 260-47 This invention relates to new and useful compositions of matter. More particularly it relates to tri-esters of hydroxy alkyl thio succinic acids of the general formula R O0.0R-SCH-C0.0R

I: ira-c 0.01a

where R is an organic radical such as phenyl, tolyl, phenylene, naphthylene, butyl, amyl, ethylene, propylene, CH=CH- benzyl, cinnamyl, anisy1,xenyl, and the like; where R is an alkylene group; and where R and R are like or unlike hydrocarbon groups comprising alkyl, aralkyl, and aryl groups. Examples of alkyl groups are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert. butyl, amyl, hexyl, octyl, decyl and dodecyl. Examples of aralkyl groups are benzyl An aryl group is illusinteger.

The new materials are readily prepared by esterifying the free hydroxy group of a hydroxy alkyl thio succinate under suitable conditions. Hydroxy alkyl thio succinates are prepared by the addition of a hydroxy substituted aliphatic mercaptan, such as mercapto ethanol, mercapto propanol, mercapto butanol, and the like, to

.maleic acid esters as described in Edward S.

Blakes copendingapplication Serial No."742,468, filed April 18, 1947, now U. S. Patent 2,477,327.

As exemplary of the preparation of the new materials the following is illustrative and in nowise is to be considered limitative thereof.

Example 1 Substantially 114 parts by weight of dibutyl maleate and substantially 39 parts by weight of mercapto ethanol were intimately mixed in a suitable reactionrvessel in the presence of 2.5 parts by weight of the catalyst sodiummethylate. An exothermic reaction set in immediately and the temperature rose to 120 of the reaction vessel were cooled below 100 C. and agitated for about one and one-half hours. Upon destroying the catalyst. with dilute acid the organic layer was taken up wjithla water immiscible solvent and thereafter washed free of acid. The solution was then dried over anhydrous sodium sulfate and filtered through a bed of Attapulgus clay. Upon removal of the solvent approximately 147 (96% of theory) parts by weight of a colorless clear liquid believed to comprise the di-butyl ester of B-hydroxy ethyl thio succinic acid was obtained. On analysis the sulfur content was found to be 1 0.67 percent (theoretical sulfur content being .10..45 percent).

C. The contents an equimolar amount of 76.5 parts by weight of the above described dibutyl ester of ,e-hydroxy ethyl thio succinic acid was intimately mixed with approximately 35.15 parts by Weight of benzoyl chloride in a reaction vessel equipped with a stirrer, thermometer, and reflux condenser and heated for 4 hours at 100- C. The contents of the vessel were further heated for one-half hour at 150 C. and then vacuum was applied for one-half hour to assure removal of the hydrogen chloride by-product, retaining the temperature at "--150 C. Upon fractionating the resultant liquid product at reduced. pressure (1 mm.) approximately 76.5% yield of an amber colored liquid acetone, alcohol, benzene, chloroform, ethyl acetate, and believed to comprise the benzoylated dibutyl esterof fi-hydroxy ethyl thio succinic acid was obtained. The structural formula of the new product is believed to be CaHsC0.0C2H4-SCHC0.0C4H0 GHQ-o 0.004117.

Example 2 Replacing di-butyl maleate of Example 1 with di-ethyl maleate and reacting in like manner with mercapto ethanol, 88.5% yield of a clear liquid product believed to zoyl chloride were intimately mixed in a reaction vessel equipped with a stirrer, thermometer, and

reflux condenser and heated for approximately Replacing di-butyl maleate of Example 1 with an equimo lar amount of di-(Z-ethyl hexyl) maleate and reacting inlike manner with mercapto ethanol, a 96% yield of a clear liquidprod- -mometer, and reflux condenserheate d for about two hours at 145l50 C. f I fhereafter vacuum was applied to assure the iemojialjoijthfihydipgen chloride by-product, Upcn fractionatingthe resultant liquid product at reduced pressure (1 mm.) approximately 87.7 percent yield of "a dark amber liquid soluble in most organic solvents and believed to comprise the benzoylated di-(Z-ethyl hexyl) ester of fi-hydroxy ethyl thio succinic acid was obtained. The structural formula 'of the new "product is"belivd t'obe came o'oinls c1r cooon;o are 211; cine 0 H o.o momma.) CQHB fidi'dmple 4 -Substantially one molecular proportioni'ofthe colorless clear'liquid di-butyl ester of B-hydroxy ethyl thio succinic acid describedinExanrple 1 was intimately mixed with-substantially'onehalf of one molecular proportion of phthalyl chloridein a reaction jvessel equipped with a stirrer, thermometer and a reflux-condenser.

While agitating the temperature was allowed to rise to 90 C. whereuponia vigorous evolutionof hydrogen chloride was'obtained. The contents of the yessel were further heated for one "hour at 145 -C. -l50 C.'and then1va'cuum was applied to assure removal of the hydrogenchloride byproduct. Upon fractionating the resultant yellow syrupy crude product at reduced pressure approximately 79.1% yield of a pale amber colored liquid, soluble in most'org'a'nic solvents and believed tocomprise di-(c ethyl thio dibutyl sucjCinate) phthal'ata'was' obtained The structiim "formula'of theiiew product is"beli'eve d'tobe c 0.0 cQHlsoH c 0.0-0m ike; 0' ng o o o @4119 e oomm's' oii-o 0.0 olizc CHE-O 0.0C4H0 "Employing" other 'acid halides lthan benzoyl chloride andphth'alyl chloridesuch' "as -toluoyl .-chloride,"*x'yloyl chloride; ethyl benz' oyl' chlorid'e,

chloride, trim'ethyl beri'zcm chloride,- plienyl fbe'nzoyl chloride, "i'iaphtliii'yl *chlori'de, naphthalyl chloride, "az'i-isyl "chloride,

"phenetyl chloride, phenylacetyl chlori e, cin- 'nam'yl ch1oride,'succinyl chloride-and the like,

in the above eiiamp'les produce, respectively; the corresponding carboxylated di-esters of the hydroxyalkyl thio succinic acids. Other methods of esterification may 'beemployed, as f hydrox'y alkyl thio succinat'es with a adder-a carboxylic acidanhydride'in e p esence of "a enema catalystfhowever; theacid halides are more effective.

The new compounds are soluble in most organic solvents and may be employed as plasticizers or softeners for such polymeric materials as polyvinyl chloride" and butaidi erie acrylonitrile"co- "poly'mers. They'haveothcr uses also ticu- *larly. useful*group is tr earoyiafi tjo hy ogerhon esters or "hydro'xy alkyl thio sticciriichcid's where the hydrocarbon groups are aliphatic groups containing not more than eight carbon "tions andmddificationsiriay'be resoif'ted fto, as for example, employing reactiontmperatures and reaction times other than those disclosed in the above examples, without departing from the spirit of thestructure is opehithqj I iWhat is claimed is:

1. As a new composition of matter a compound tiie stmcmre where R, is hydrocarbon radical containing at least Z'Lbut not more than 12 carbon atomsfliaving' a valence less than three; -'R'; is; an 'alkylene :group' of less than fivecarbon atoms; R'.::' and I Q I I where R is an aryI hydrjocarbong' ing at least 6' butnot morejthanjl2 ca having a valence less than threegBfis',anialkylen group of less than live carb atoms, 13 and RQ e d 'e 'r n sent i if i l i ilea .1 carbon atoms and ms 'an integer at least one but less than three I.

'1 c 3. As a newcom'position of matter a compound of'the'structure a H v g v u c6i14[o O.OC2H;SOH-C 0.0a]

v I daemo '2 w os an F BQ HDh cbY containi'righot more than'eigh y 4; Asa new composition of mattera'com of the structure 7 h OeHaCQOCzHr-S-CHOODR "'oHlo'o'LoR' where R and R arealiphatic hydrocarbongroups containing not more than'eight carbon atoms. 5 As a new composition of matter a compound of the structure CGHaC o o o ga s c 11o 0. o c2115 7 celeb" "5 gas-Agenc eompositienbrmaaeracombbuiia O r 'orcc 07o o'l-Hq 7. As anew. composition of mattera compound of the stru'cture I 5 p camedocings encoiaelei onlo-otoognt i ig'ni iie' singin claim 1 were cri swr d s swi hi e of; hydrogen clilor ide the' acid '0 "de fof 'd' erben erh rrl earlier V WW inier f h l carbine; de t m e heniw f r'b r ms. a H. hydroxyalkylthiosuccinate havingnot'more' man four carbon atoms in the hydroxyalkyl group and in which both carboxyl groups are esterified by hydrocarbon groups containing less than 13 carbon atoms.

9. The method of making the composition of claim 2 which comprises condensing with removal of hydrogen chloride the acid chloride of an arcmatic hydrocarbon carboxylic acid in which the hydrocarbon group contains at least 6 but not more than 12 carbon atoms substituted by not more than two carboxyl groups and an hydroxyalkylthiosuccinate having not more than four carbon atoms in the hydroxyalkyl group and in which both carboxyl groups are esterfied by hydrocarbon groups containing less than 13 carbon atoms.

10. The method of making the composition of claim 3 which comprises condensing phthalyl chloride with fl-hydroxy ethyl thio succinate wherein both carboxyl groups are esterified with aliphatic hydrocarbon groups containing not more than eight carbon atoms.

11. The method of making the composition of claim 4 which comprises condensing benzoyl chloride with fl-hydroxy ethyl thio succinate wherein both carboxyl groups are esterified with aliphatic hydrocarbon groups containing not more than eight carbon atoms.

12. The method of making the composition of claim 5 which comprises condensing benzoyl chloride with the di-ethyl ester of p-hydroxy ethyl thio succinic acid.

13. The method of making the composition of claim 6 which comprises condensing benzoyl chloride with the di-butyl ester of fl-hydroxy ethyl thio succinic acid.

14. The method of making the composition 01' claim 7 which comprises condensing benzoyl chloride with the di-octyl ester of ,B-hydroxy ethyl thio succinic acid.

RICHARD O. ZERBE.

Country Date Great Britain Jan. 4, 1934 Number Number 

1. AS A NEW COMPOSITION OF MATTER A COMPOUND OF THE STRUCTURE 